Scoliosis research society outcome instrument in evaluation of long-term surgical results in spondylolysis and low-grade isthmic spondylolisthesis in young patients.

STUDY DESIGN: A retrospective follow-up study of low-grade (slip < or = 50%) isthmic spondylolisthesis after posterior or posterolateral fusion in young patients.

OBJECTIVE: To evaluate the usefulness of the Scoliosis Research Society questionnaire and compare it with Oswestry Disability Index and radiographic parameters in patients with isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA: A few studies have examined long-term patient outcome using validated questionnaires or compared it with radiographic parameters after surgery for isthmic spondylolisthesis in young patients. The Scoliosis Research Society questionnaire provides patient-oriented information on back pain, cosmetic aspects, patient satisfaction, and level of activity and might therefore be suitable for evaluation of surgical outcome after isthmic spondylolisthesis in young patients. However, there are no studies assessing the usefulness of the Scoliosis Research Society questionnaire for these patients.

METHODS: One hundred and eight patients treated at a mean (range) age of 15.9 (range, 8.1-19.8) years with posterior (n = 29) or posterolateral (n = 79) in situ fusion for isthmic spondylolisthesis participated in the present study. The follow-up rate was 83% after a mean of 20.8 (range, 15.1-25.9) years. The mean age at follow-up observation was 36.7 years. Radiographs were obtained before surgery, at 2-year follow-up observation, and at final follow-up review. The Scoliosis Research Society and Oswestry Disability Index questionnaires were completed, and a physical examination was performed at the final follow-up visit.

RESULTS: Nonunion after primary operation was found in 10 (34%) patients after posterior fusion and in 10 (13%) patients after posterolateral fusion (P = 0.0017). The mean (range) anterior slip was 25.2% (0-50%) before surgery and 24.2% (0-78%) at final follow-up observation. Lumbosacral kyphosis increased significantly during the follow-up period. The Scoliosis Research Society questionnaire yielded a total of 94.0 (range, 44-114) points. On the Scoliosis Research Society questionnaire, 14 (14%) patients reported back pain often or very often at rest. The Oswestry Disability Index scores averaged 8.2 (range, 0-68). There was a significant correlation between the Scoliosis Research Society total score and the Oswestry Disability Index. The percentage slip showed significant inverse correlations with the scores for appearance in clothes, attractiveness, and self image (Scoliosis Research Society questions 5, 14, and 15).

CONCLUSIONS: Long-term clinical and radiographic outcomes after posterolateral fusion of low-grade spondylolisthesis were satisfactory. Cosmetic aspects of this deformity should be included as one of the outcome measurements, since cosmetic questions on the Scoliosis Research Society questionnaire showed inverse correlations between the amount of slip at final follow-up observation. The Scoliosis Research Society questionnaire could be used as a primary patient-oriented outcome tool after back surgery in young patients.